JP3795988B2 - How to build a pipe roof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing a pipe roof, and more particularly to a method for constructing a pipe roof by preventing groundwater from flowing into a start shaft and propelling a plurality of propulsion pipes.
[0002]
[Prior art]
When a tunnel is constructed across a bank, road, or railroad embankment, a propulsion pipe with a joint formed on the outer circumference or inner circumference is propelled in the direction crossing the embankment, and the propulsion pipe already buried A new propulsion pipe is disposed adjacent to the pipe, and the joint of the new propulsion pipe is engaged with the joint of the propulsion pipe that has already been propelled and sequentially buried, thereby connecting to each other via the joint. A so-called pipe roof for supporting the ground by a plurality of propulsion pipes embedded therein is also being constructed.
[0003]
The propulsion pipe used when constructing the pipe roof has a pair of joints extending over the entire length and formed at predetermined positions on the outer periphery or the inner periphery. This joint is generally composed of a male joint made of T-shaped steel welded to the outer periphery of the propulsion pipe and a female joint similarly welded with two angle steels facing the flange on the outer periphery of the propulsion pipe. It is. Recently, however, we have also provided a propulsion pipe (actual No. 8-3515) in which a grooved steel flange is welded to the inner peripheral surface and a slit is formed in the propulsion pipe between the flanges to form a female joint. Has been.
[0004]
When constructing a pipe roof, a retaining wall is formed on the starting side, and each time the propulsion pipe is propelled, a hole with a diameter larger than the diameter of the propulsion pipe is continuously formed in the retaining wall. Formed. That is, the earth retaining wall is divided at the propulsion part of the propulsion pipe, and in particular, there is a possibility that the earth retaining part above the propulsion pipe becomes unstable.
[0005]
On the other hand, recently, it is increasingly required to construct a pipe roof in the ground where groundwater exists. In this case, there arises a problem that the joint formed in the propulsion pipe functions as a dredger and the groundwater flows into the start shaft.
[0006]
For this reason, the present applicant has developed a technology that can solve the above problems and has applied for a patent. For example, in the technology disclosed in Japanese Patent No. 2529644, each time a digging machine and a propelling pipe are propelled, a mold is formed around the portion to be propelled, and the digging machine is arranged in the formwork and the digging machine is arranged. After placing a member corresponding to the joint of the propulsion pipe and an elastically deformable member around the periphery, the concrete is cast and the upper and lower earth retaining walls are integrated, and the elastically deformable member is the excavator and the propulsion pipe It is configured to prevent outflow of groundwater from the surroundings to the start shaft
[0007]
[Problems to be solved by the invention]
However, even if it is the above-mentioned invention, it is not perfect yet, and after propelling one propulsion pipe, when propelling a new propulsion pipe adjacent to the propulsion pipe, the side connecting the new propulsion pipe The formwork is removed to expose only the joint, and the joint of the new propulsion pipe is engaged with the joint. However, it is difficult to seal the joint portion of the joint that has been engaged. There is a problem that groundwater flows into the start shaft.
[0008]
The objective of this invention is providing the construction method of the pipe roof which can prevent inflow of the groundwater etc. with respect to a starting shaft.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, a pipe roof construction method according to the present invention includes a plurality of propulsion pipes that form joint portions over the entire length in the longitudinal direction, and the joint portions are engaged with each other and laid in the ground in parallel. A method for constructing a pipe roof, the mirror cutting step of forming a hole having a diameter larger than the diameter of the propulsion pipe at a position where the propulsion pipe in the retaining wall of the start shaft is to be propelled, A frame attaching step for fixing a frame composed of right and left side surfaces and a bottom surface around a mirror-cut portion, and a main pushing device is installed facing the mirror-cut hole and mounted on the main pushing device. A mechanical installation step of inserting the tip portion of the pierce into the hole, and a porous sheet having elasticity and a predetermined thickness is wound around the outer periphery of the excavator by a band, and a joint portion is provided on the outer periphery of the propulsion pipe. If it is formed protruding A blind member having a shape substantially equal to the cross-sectional shape of the joint portion is arranged at a position corresponding to the joint portion formed on the outer periphery of the excavator and between the sheet and the outer periphery of the propulsion pipe. A water stopping process, a casting process in which the front surface of the frame fixed to the retaining wall is closed to form a mold, and mortar or concrete is cast on the mold, and mortar or concrete is cast on the mold After that, a propulsion step of propelling the excavator and propelling the propulsion pipe following the excavator for a predetermined length, and after the completion of the propulsion step, the formwork on the joint portion side in the propulsion tube already propelled Part of the mortar or concrete and part of the sheet are removed to expose the part of the outer periphery of the propelled pipe and the joint, and the propulsion is already carried out on the retaining wall of the start shaft A new propulsion pipe adjacent to the The frame was fixed around the part of the propulsion tube that had been propelled and partly removed, and the frame was fixed to the earth retaining wall and had a diameter larger than that of the propulsion pipe. A hole is formed, and then a main pushing device is installed so as to face the hole, and a tip portion of an excavator mounted on the main pushing device is inserted into the hole, and then the sheet is banded on the outer periphery of the excavator And when the sheet is connected to a sheet arranged around the propelled pipe already propelled and a joint is formed on the outer periphery of a new propulsion pipe, the cross-sectional shape of the joint A blind member having a shape substantially equal to the outer periphery of the excavator is disposed at a position corresponding to a joint portion formed between the sheet and the outer periphery of the propulsion pipe. Formwork formed around the propulsion pipe And continuously closing the front surface of the frame fixed to the earth retaining wall to form a mold and placing mortar or concrete on the mold, and then propelling the excavator and adding a new one to the excavator And a new propulsion pipe propulsion step in which the propulsion pipe is followed and the joint portion of the propulsion pipe is engaged with the joint portion of the propulsion pipe that has already been propelled to propel the predetermined length. This propulsion process is repeated.
[0010]
In the above-described pipe roof construction method, a frame having both side surfaces and a bottom surface is fixed to the retaining wall prior to propulsion of the propulsion pipe, so that the retaining wall around the propulsion part is connected by the frame. Mirror cutting is performed to form a hole in the earth retaining wall inside, the main pushing device and the excavator are opposed to the hole, and the tip portion of the excavator is inserted into the hole, on the outer periphery of the excavator A porous sheet having elasticity and a predetermined thickness is wound with a band. Then, the open part formed between the front surface of the frame and the outer periphery of the excavator is closed to form a mold with the upper part opened. By placing mortar or concrete (hereinafter referred to as “concrete”) on the mold, the upper and lower sides of the hole can be integrated with the mold and the concrete.
[0011]
Concrete cement milk placed in the mold is impregnated into the holes of the sheet wound around the outer periphery of the excavator and solidifies. At this time, the outer peripheral side (concrete side) of the sheet is integrated with the cast concrete with sufficiently high strength, and the inner peripheral side (outer peripheral side of the excavator) maintains elasticity.
[0012]
Therefore, after the concrete placed in the mold is solidified, when the excavator is propelled, the sheet can be brought into frictional contact with the outer peripheral surface of the excavator and water can be stopped between the two. Also, when propelling the propulsion pipe following the excavator, the sheet can be similarly brought into frictional contact with the outer peripheral surface of the propulsion pipe to stop the water between them and prevent outflow of groundwater or the like.
[0013]
After laying the propulsion pipe between the compatible pits through the propulsion process of propelling the propulsion pipe from the start pit side to the arrival pit side as described above, in the exposure process, the propulsion pipe is adjacent to the propulsion pipe (existing pipe). When a new propulsion pipe (new pipe) is propelled, the formwork and concrete on the side of the existing pipe connecting the new pipe are removed. At this time, the concrete and the sheet are not removed up to the joint of the existing pipe, but are removed until a part of the joint and the existing pipe is exposed.
[0014]
After exposing the joint of the existing pipe and a part of the outer peripheral surface as described above, the frame is again fixed to the retaining wall so as to correspond to the propulsion part of the new pipe, and further, it is formed by mirror cutting. A main pushing device is installed to face the hole, and a digging machine is attached to the main pushing device, and the tip is inserted into the hole. In this state, a blind member is attached to a predetermined position on the outer periphery, and the sheet is wound. By connecting the end of this to a sheet arranged around the existing pipe and fixing with a band, the sheet arranged around the existing pipe and the sheet arranged around the new pipe are integrated.
[0015]
After that, the open part formed on the front surface of the frame formed around the new pipe is closed to form a formwork with one side exposed to the concrete formed around the existing pipe. To cast. Concrete cement milk placed in a formwork placed around the new pipe impregnates the hole in the sheet, and as the concrete solidifies, the concrete and the sheet are firmly integrated, and the existing pipe sheet and new Integrate the tube sheet.
[0016]
As described above, the excavator is arranged adjacent to the existing pipe, and the new pipe is followed by the new pipe and the joint of the new pipe is engaged with the joint of the existing pipe and propelled. Tubes can be laid in the ground.
[0017]
Therefore, a pipe roof can be constructed by repeating the above procedure every time a propulsion pipe is laid. In particular, when a new pipe is adjacent to an existing pipe, the concrete placed around the existing pipe is removed to expose the joint and a part of the existing pipe to connect the sheet. It is possible to maintain high sealing performance in close contact with the joint and prevent groundwater from flowing out to the start shaft side.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the pipe roof construction method will be described with reference to the drawings. 1 is a schematic diagram for explaining a state of propelling a propulsion pipe, FIG. 2 is a diagram for explaining a procedure for propelling the propulsion pipe, and FIG. 3 is a propulsion pipe adjacent to the propulsion pipe that has already been propelled. FIG. 4 is a diagram for explaining the connection procedure of the formwork, FIG. 4 is a diagram for explaining the relationship between the propelled pipe already propelled and the sheet applied to the new propelled pipe, and FIG. 5 is a joint of the propelled pipe already propelled. It is a figure explaining the state propelled by engaging the joint of a new propulsion pipe.
[0019]
In the pipe roof construction method according to the present invention, when constructing a pipe roof in the ground, prior to propelling the excavator, concrete is placed around the excavator so that the earth retaining wall is integrated vertically. Even when a new pipe is propelled adjacent to an existing pipe, the groundwater is prevented from flowing out from the joint portion of these pipes to the start shaft side. Is.
[0020]
Prior to explaining the construction method of the pipe roof according to the present invention, a propulsion method for propelling the propelling pipe A and laying it in the ground will be briefly explained with reference to FIG. In the propulsion method, the propulsion pipe A that follows the excavator B is propelled by the main pusher D installed in the start shaft C, so that it is propelled from the start shaft C toward an arrival shaft (not shown).
[0021]
The start shaft C is installed at a preset depth, and a surrounding wall 1 is configured by driving a steel sheet pile around. A wellhead E is formed at a predetermined position of the retaining wall 1. The wellhead E integrates the earth retaining wall 1 divided by the excavator B and the propelling pipe A, and prevents the inflow of groundwater to the starting vertical shaft C, and is configured as described later.
[0022]
The excavator B excavates a natural ground, and includes a shield body 3 provided with a cutter head 2 at the tip, and a tail shield 4 connected to the shield body 3 in a refractive manner. Further, the main pushing device D applies thrust to the excavator B and the propulsion pipe A following the excavator B and propels them into the ground. The excavator B and the propulsion pipe A are mounted and moved. A platform 5 that guides the direction, a push wheel 6 that transmits thrust by moving the platform 5 in contact with the rear ends of the excavator B and the propulsion pipe A, and a jack 7 that drives the push wheel 6 are provided. Configured.
[0023]
In the above configuration, the excavator B is mounted on the gantry 5 of the main pusher D, the jack 7 is driven to advance the push wheel 6 to apply thrust to the excavator B, and the cutter of the excavator B By driving the head 2 and excavating the natural ground, the excavator B can be propelled to the natural ground. Then, after the propulsion of the excavator B is completed, the push ring 6 is pulled back, the propulsion pipe A is mounted on the gantry 5 and the push ring 6 is advanced again, so that the excavator B is followed by the propulsion pipe A and the ground. Can be promoted.
[0024]
Therefore, by repeating the above procedure every time the propulsion pipe A is propelled, the propulsion pipe A can be propelled toward the arrival shaft and laid in the ground.
[0025]
When constructing a pipe roof, it is necessary to propel a plurality of propulsion pipes A according to the target pipe roof. In particular, the positional accuracy of the propelled propelling pipe A is preferably sufficiently high. Therefore, as shown in FIG. 5, the reference propulsion pipe Aa is propelled at a preset position while maintaining sufficiently high positional accuracy, and new propulsion pipes Ab are sequentially adjacent to both sides of the propulsion pipe Aa. Thus, the accuracy of the propulsion pipe Ab and the propulsion pipe Ab with respect to the propulsion pipe Aa is maintained. Then, it is possible to construct a tunnel by excavating the inside of the constructed pipe roof to remove earth and sand, and then constructing a peripheral wall by selectively placing concrete according to the purpose.
[0026]
Next, the structure of the propulsion pipes Aa and Ab used in this embodiment will be described with reference to FIG. As shown in the drawing, a generally used propulsion pipe Ab has a pipe part constituting member 12 made of grooved steel having a flange 12a and a web 12b over the entire length inside the raw pipe 11, and the flange 12a is the raw pipe 1 It is welded in a state where it is in contact with. Further, the portion corresponding to the space between the flanges 12a of the pipe part constituting member 12 of the elementary pipe 11 has a predetermined width over the entire length (a width dimension that is sufficiently wider than the thickness of the T-shaped steel web 14b constituting the male joint 14 described later). A groove 11a is formed. A female joint 13 is constituted by the pipe portion constituting member 12 and the groove 11a.
[0027]
A male joint 14 is formed at a position on the outer periphery of the raw tube 11 with a position where the female joint 12 is formed as a reference and according to an arrangement position on the target pipe roof. The male joint 14 includes a flange 14a having a dimension smaller than the dimension between the flanges 12a of the pipe partial component 12 constituting the female joint 13, and a web 14b fitted into the groove 11a of the base pipe 11. It is formed into a shape. Therefore, the width dimension of the groove 11a formed over the entire length of the raw tube 11 has a value that allows the web 14b of the male joint 14 to be easily fitted.
[0028]
Further, the propulsion pipe Aa propelled to a position serving as a reference for the pipe roof is formed inside the base pipe 11 and two female joints 13 are formed at predetermined positions. Therefore, when propelling the propelling pipe Aa, no projections are formed on the outer circumference of the pipe Aa, so that there is no resistance to natural ground, and there are few occurrences of bending or rolling during propulsion, and high-accuracy propulsion. Can be done.
[0029]
Next, a procedure for constructing a pipe roof by propelling the propulsion pipes Aa and Ab will be described with reference to the drawings. First, the reference propulsion pipe Aa is propelled to a preset position in the pipe roof. Then, the male pipe 14 is fitted to the female joint 13 of the propelling pipe Aa on both sides of the propelling pipe Aa propelled to the reference position, and the propelling pipe Ab is propelled.
[0030]
2A and 2B show a mirror cutting process. In this step, a hole 21 is formed in the earth retaining wall 1 and ground of the start shaft C. The hole 21 is formed with a diameter larger than the diameter of the excavator B (propulsion pipe Aa) corresponding to a reference position when constructing the pipe roof.
[0031]
When the mirror cutting step is completed, in the frame attaching step shown in FIG. 3C, the frame 22 composed of the left and right side surfaces 22a (see FIG. 3) and the bottom surface 22b is fixed around the hole 21. The frame 22 constitutes the wellhead E, and exhibits a function as a mold when casting concrete. The fixing method of the frame 22 to the retaining wall 1 is set according to the structure of the retaining wall 1. That is, when the earth retaining wall 1 is constituted by a steel sheet pile, the frame 22 is welded to the steel sheet pile. Further, when the earth retaining wall 1 is made of concrete, the frame 22 is welded to a core made of a reinforced steel bar or shaped steel.
[0032]
The mirror cutting process and the frame attaching process are not necessarily performed in the order of this embodiment, and the frame attaching process may be performed first.
[0033]
After the frame 22 is fixed to the earth retaining wall 1, a machine installation process is performed. First, the main pushing device D is made to face the hole 21, and the machine center is installed on the start shaft C so as to coincide with the core 23 of the propulsion pipe Aa. Then, by mounting the excavator B on the gantry 5 of the main pushing device D, the machine center of the excavator B coincides with the core 23 as shown in FIG. At this time, the tip side of the excavator B is covered with a bag 24 for preventing the penetration of concrete into the cutter head 2. Next, as shown in FIG. 5E, the excavator B is pushed into the hole 21 so that the outer peripheral portion of the excavator B corresponds to the frame 22.
[0034]
Next, in the water stop process, as shown in FIG. 5F, an elastic and porous sheet 25 having a predetermined thickness is wound around the outer periphery of the excavator B, and this sheet 25 is wound on the band 26. And fastened by a turnbuckle 26a. When the excavator B and the propelling pipe A are propelled, the seat 25 stops on the frame 22 and elastically contacts with the outer peripheral surface of the excavating machine B and the propelling pipe A, so that the groundwater from the natural ground to the starting shaft is obtained. It has a function to prevent inflow.
[0035]
As will be described later, when concrete is placed in a formwork as described later, the sheet 25 is impregnated with cement milk in a large number of holes, and about half of the thickness is cured to be integrated with the concrete. It is preferable that about half of them retain elasticity. For this reason, it is preferable that the holes formed in the sheet 25 are not so-called continuous holes that are continuous in the thickness direction but so-called single holes that are appropriately divided. The thickness varies depending on the diameters of the excavator B and the propelling pipe A, but is preferably about 50 mm. Such a sheet 25 includes a synthetic resin foam, such as a sponge.
[0036]
After the sheet 25 is wound around the excavator B and fixed with the band 26 as described above, the outer periphery of the excavator B on the front side of the frame 22 as shown in FIGS. A packing 27 is attached to the open portion formed between the two, and the packing 27 is tightened with a fastening bracket 28 to close the front surface. As a result, a mold frame 29 composed of the frame 22, the earth retaining wall 1 and the packing 27 and having an open upper surface is formed.
[0037]
Next, in the placing step shown in FIG. 5 (i), concrete 30 is placed on the mold 29, thereby forming a hole E. The concrete 30 placed in the mold 29 is also poured into the ground through the hole 21, but the tip side of the excavator B is covered with the bag 24, so that the excavator B is adversely affected. There is nothing.
[0038]
As described above, after the concrete 30 is placed on the mold 29 and a predetermined curing period has elapsed, the propulsion process is performed. In this step, as described above, the cutter head 2 of the excavator B is driven to drive the jack 7 of the main pushing device D while excavating the natural ground, and the thrust of the jack 7 is excavated through the push ring 6. It is performed by giving to machine B.
[0039]
When propelling the excavator B, since the outer peripheral surface side is integrated with the concrete 30 and the inner peripheral surface side is elastic, the sheet 25 is elastically pressed against the outer peripheral surface of the excavator B and exhibits a sealing function. . For this reason, groundwater in the natural ground does not flow between the excavator B and the seat 25 and flows into the start shaft C side.
[0040]
When the propulsion of the excavator B is completed, the jack 7 of the main pushing device D is driven to pull the push wheel 6 back, and the propulsion pipe Aa is mounted on the gantry 5. Thereafter, the jack 7 is again driven forward to connect the propulsion pipe Aa to the rear end of the excavator B and propel both. By repeating this operation, the propulsion pipe Aa is propelled to the arrival shaft, and the propulsion ends with the end of the propulsion pipe Aa protruding from the compatible mine. FIG. 3A shows a state where the propulsion of the propulsion pipe Aa on the start shaft C side is completed. When propelling the propelling pipe Aa, it is preferable to insert a synthetic resin foam having appropriate elasticity, such as foamed polyethylene, into the female joint 14.
[0041]
Next, regarding the procedure for propelling a new propulsion pipe (new pipe) Ab adjacent to the existing pipe Aa, the propulsion pipe Aa serving as a reference for the pipe roof propelled as described above is the existing pipe Aa. explain. As shown in FIG. 3A, when the existing pipe Aa is propelled, the rear end of the existing pipe Aa protrudes into the start shaft C.
[0042]
When the male joint 14 of the new pipe Ab is engaged with the female joint 13 on one side of the existing pipe Aa for propulsion, the frame 22 on the side connecting the new pipe Ab is cut as shown in FIG. At the same time, the concrete 30 is removed to expose the female joint 13 of the existing pipe Aa, a part of the outer peripheral surface of the existing pipe Aa, and a part of the sheet 25.
[0043]
At this time, it is necessary not to expose only the groove 11a of the element 11 constituting the female joint 13, but to expose the outer periphery of the existing pipe Aa together with the seat 25 in a sufficiently wide range. In this case, it is not necessary to remove all the sheets 25 arranged on the outer peripheral surface of the existing pipe Aa, and it is preferable to leave the sheets 25 other than the peripheral part of the female joint 13.
[0044]
After the outer periphery of the existing pipe Aa is exposed as described above, a hole 21 is formed at a position adjacent to the existing pipe Aa of the earth retaining wall 1 as shown in FIG. Further, one side surface forms an outer periphery of the existing pipe Aa and a frame 22 using the concrete 30. When forming the frame 22, the bottom plate 22b is welded and integrated with the bottom plate 22b of the frame 22 formed around the existing pipe Aa.
[0045]
After the frame 22 is formed as described above, the main pushing device D is installed facing the hole 21 in the same manner as the procedure for propelling the propelling pipe Aa, and the excavator B is mounted on the main pushing device D. Then, the tip is covered with the bag 24 and pushed into the hole 21. At this time, since the position and parallelism of the excavator B with respect to the existing pipe Aa are important factors for guaranteeing accuracy when the new pipe Ab is propelled, it is necessary to set it strictly.
[0046]
After the position of the excavator B with respect to the existing pipe Aa is set, FIG. 4 and FIG. 5 (these drawings show a state in which the male joint 14 of the new pipe Ab is engaged with the female joint 13 of the existing pipe Aa. However, as shown in the figure, the excavator B is assumed instead of the new pipe Ab.) As shown in FIG. The band 31 has a length shorter than ½ of the outer circumference of the excavator B, a screw that can be screwed into the turnbuckle 31a is formed at one end, and the existing end is provided at the other end. A hook 31b is provided which is fitted in the groove 11a of the element 11 constituting the female joint 13 of the pipe Aa and is locked to the element 11.
[0047]
Accordingly, the sheet 25 arranged on the outer periphery of the existing pipe Aa is cut in the vicinity of the female joint 13 of the pipe Aa, and the pair of bands 31 are engaged with the respective hooks 31b in the grooves 11a of the existing pipe Aa. It is possible to connect the new sheet 25 to the sheet 25 of the existing pipe Aa by winding around the outer periphery of the sheet 25 arranged on the outer periphery of the new pipe Ab and fastening with the turnbuckle 31a.
[0048]
After that, after installing packing 27 on the front surface of the frame 22, the concrete well 30 is cast to form the wellhead E. After the concrete 30 is cured, the excavator B is promoted and the new pipe Ab is subsequently promoted. To do.
[0049]
As described above, when the female joint 13 of the existing pipe Aa is engaged with the male joint 14 of the new pipe Ab and propelled as described above, the groove 11a of the female joint 13 of the existing pipe Aa is seated around the outer periphery of the new pipe Ab. Since the female joint 13 is previously closed with foam, groundwater does not flow through the female joint 13 and flow into the start shaft C.
[0050]
In the above embodiment, the propulsion pipes Aa and Ab are configured so that the joint does not protrude during propulsion. However, not all of the propulsion pipes for constructing the pipe roof are such that the joint protrudes, and there are some in which a female joint is constructed by welding C-shape steel or angle steel to the outer periphery of the base metal. When such a propulsion pipe is used, a foam having a shape equal to the cross-sectional shape of the joint projecting on the outer periphery of the excavator B is attached, and the sheet 25 is wound from the outside of the foam to promote the propulsion. It is possible for the seat to safely avoid the joint when propelling the tube.
[0051]
【The invention's effect】
As explained in detail above, in the method for constructing a pipe roof according to the present invention, when a new pipe is adjacent to an existing pipe and propelled, the formwork and concrete existing on the joint side of the existing pipe are removed to remove the joint. After exposing a part of the outer periphery of the propulsion pipe and the sheet, engaging the sheet wound around the new pipe with this exposed part to stop the water, and then placing concrete on the formwork to make the excavator and propulsion pipe Therefore, the retaining wall divided by the excavating machine and the propelling pipe can be integrated by the mold fixed to the retaining wall and the concrete cast on the mold.
[0052]
For this reason, since the sheet placed between the excavator and the propulsion pipe and the concrete can be kept connected to the sheet of the existing pipe that has already been propelled, the groundwater is placed between the excavator and the concrete on the start shaft side Will not flow into. Further, even when the target pipe roof is installed in the ground, and the starting shaft is constructed underground, the retaining wall can exhibit a stable strength.
[Brief description of the drawings]
FIG. 1 is a schematic diagram for explaining a state in which a propulsion pipe is propelled.
FIG. 2 is a diagram illustrating a procedure for propelling a propulsion pipe.
FIG. 3 is a diagram for explaining a procedure for connecting a formwork when propelling a new propelling pipe adjacent to a propelled pipe that has already been propelled.
FIG. 4 is a diagram for explaining a relationship between a propulsion pipe that has already been propelled and a seat that is applied to a new propulsion pipe.
FIG. 5 is a diagram for explaining a state in which a new propulsion pipe joint is engaged with a propulsion pipe joint that has already been propelled and propelled.
[Explanation of symbols]
A, Aa, Ab propulsion pipe
B digging machine
C Starting shaft
D original pusher
E wellhead
1 Earth retaining wall
2 Cutter head
3 Shield body
4 Tail shield
5 frame
6 Push ring
7 Jack
11 Elementary tube
12 Tube component parts
13 Female fitting
14 Male fitting
21 holes
22 frames
23 cores
24 bags
25 seats
26, 31 bands
26a, 31a Turnbuckle
27 Packing
28 Fastening bracket
29 formwork
30 concrete
31c hook

Claims (1)

A method for constructing a pipe roof by laying a plurality of propulsion pipes that form joint portions over the entire length in the longitudinal direction in parallel with the joint portions engaged with each other,
A mirror cutting process for forming a hole having a diameter larger than the diameter of the propulsion pipe at a position where the propulsion pipe in the retaining wall of the start shaft is to be propelled;
A frame attaching step for fixing a frame composed of left and right side surfaces and a bottom surface around the mirror-cut portion;
A machine installation step of installing a main pushing device facing the mirror cut hole and inserting a tip portion of an excavator attached to the main pushing device into the hole;
In the case where a porous sheet having elasticity and a predetermined thickness is wound around the outer periphery of the excavator by a band, and a joint portion is formed so as to protrude from the outer periphery of the propulsion pipe, a cross section of the joint portion A water stopping step in which a blind member having a shape substantially equal to the shape is disposed on the outer periphery of the excavator and at a position corresponding to a joint formed between the sheet and the outer periphery of the propulsion pipe; ,
A placing step of closing a front surface of the frame fixed to the earth retaining wall to form a mold and placing mortar or concrete on the mold;
After placing mortar or concrete in the formwork, the propulsion step of propelling the excavator and propelling the propulsion pipe following the excavator for a predetermined length;
After the propulsion step is completed, a part of the mold on the joint side and part of the mortar or concrete and the sheet in the propelled pipe that has been propelled are removed, and the outer circumference of the propelled pipe that has already been propelled is removed. A tube exposure process for exposing the joint portion and the joint portion;
Formwork formed around the already propelled pipe and partly removed around the area where the new propelled pipe adjacent to the already propelled pipe on the earth retaining wall of the start shaft is to be propelled And a hole with a diameter larger than the diameter of the propulsion pipe is formed in the retaining wall, and then a main pushing device is installed facing the hole and attached to the pushing device. The leading end portion of the excavator is inserted into the hole, and then the sheet is wound around the outer periphery of the excavator by a band, and the sheet is connected to a sheet disposed around the propelled pipe that has already been propelled. When the joint portion is formed so as to protrude from the outer periphery of the propulsion pipe, a blind member having a shape substantially equal to the cross-sectional shape of the joint portion is disposed between the outer periphery of the excavator and the seat and the propulsion pipe. Joints formed on the outer periphery of Next, the formwork is formed by closing the front face of the frame fixed to the retaining wall continuously with the formwork formed around the propelled pipe that has already been propelled. Mortar or concrete is then placed on, and then the excavator is propelled and the excavator is followed by a new propelling pipe and the joint of the propelling pipe is engaged with the joint of the propelled pipe already propelled Including a new propulsion pipe propulsion process for a predetermined length,
Thereafter, the pipe roof construction method is characterized in that the propulsion process of the new propulsion pipe is repeated.

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